Browsing by Issue Date, starting with "1995"

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Ion transport studies in PEO:NH4I polymer electrolytes with dispersed Al2O3
(Kluwer Academic Publishers, 1995) A. Chandra; P.C. Srivastava; S. Chandra
Ion conducting polymer electrolyte films having high salt concentrations have been studied. The system studied is PEO:NH4I, dispersed with α-Al2O3. Mechanically stable films with NH4+/EO ratio ≥0.13 have been obtained by dispersal of Al2O3. The films have been characterized using various techniques such as X-ray diffraction (XRD), differential thermal analysis (DTA), polarization and complex impedance spectroscopy. Intercorrelation between polymer matrix crystallite size, conductivity, and α-Al2O3 particle size is established. © 1995 Chapman & Hall.
Changes in lipid profiles and 32P-uptake into phosphoprotein (vitellogenin) content of the ovary and liver in the female catfish, Clarias batrachus, exposed to mercury.
(1995) R. Kirubagaran; K.P. Joy
Toxic effects of selected sublethal concentrations of mercuric chloride (HgCl2, 0.05 mg.L-1), methylmercuric chloride (CH3HgCl, 0.04 mg.L-1) and Emisan 6 (an organic mercurial fungicide, 0.5 mg.L-1) on levels of lipids (total lipids-TL, phospholipids-PL, free cholesterol-FC; esterified cholesterol-EC and free fatty acids-FFA), and uptake of 32P into phosphoprotein fraction of the ovary and liver are reported in Clarias batrachus exposed for 45, 90 and 180 days from February to July (preparatory to spawning phase of the annual reproductive cycle). The TL level decreased significantly only in the ovary of 180-day Hg groups. The ovarian PL and FC levels showed a significant reduction at all durations of Hg exposure. In contrast, the hepatic PL and FC levels increased significantly at all durations except the PL content in the 45-day Emisan 6 and CH3HgCl groups. The EC level in the ovary showed a significant decline after both 90 and 180 days of Hg treatment whereas in the liver, it decreased significantly only after 180 days. The level of FFA in the ovary decreased significantly only in the 180-day HgCl2 group while in the liver, it showed a significant increase in all the 180-day Hg groups. The rate and level of incorporation of 32P into phosphoprotein fraction of the ovary and liver showed a progressive decline in the Hg-treated groups, the effect being significantly different only after 90 and 180 days. The results suggest that the decrease in ovarian lipid levels is largely due to their immobilization from the liver and the reduction in vitellogenin content may be due to both the inhibition of its synthesis in the liver and subsequent incorporation into the ovary.
Far field patterns of hollow dielectric wall diagonal horn antennas
(IEEE, 1995) V.N. Tiwari; T. Tiwari; S.P. Singh; R.K. Jha
In this paper, far field patterns of hollow dielectric wall diagonal horn antennas of various thicknesses (0.15, 0.15, 0.32 and 0.32 cm) and dielectric constants (ε′ = 2.54, 2.56, 2.56 and 3.03) are studied both theoretically and experimentally at 9.418 GHZ. Theoretical near field distribution at the aperture and at the side surfaces of a horn under study for TE to x and TE to y modes are obtained by solving the Helmholtz's equation using separation of variables technique. The expressions for the near field components of the horn under study are used to obtain the expression for radiation pattern from the Kirchoff's diffraction formula. The theoretical far field patterns obtained for these antennas are compared with corresponding experimental ones.
Allowed-unhindered β decay of Yb180 and the nuclear structure of Lu180
(1995) F. Meissner; T. Hild; V. Kunze; W.-D. Schmidt-Ott; C. Wennemann; P.C. Sood; R. Kirchner; E. Roeckl; K. Rykaczewski
The β decay of mass-separated Yb180 was investigated by measuring β-delayed γ rays and conversion electrons. Evidence was found for an allowed-unhindered β transition involving the transformation of a 7/2-[514] neutron into a 9/2-[514] proton. The experimental results include a new decay scheme of Yb180 which gives evidence for a 5+ ground state of Lu180 and leads to the first identification of further low-spin configurations. These data are compared with predictions obtained from two-quasiparticle band-head energy calculations based on a zero-range residual interaction with appropriate Nilsson model wave functions. © 1995 The American Physical Society.
Growth and characterization of single crystals in the series ZrSxSe2-x
(1995) K.S. Bartwal; O.N. Srivastava
Single crystals of transition metal dichalcogenide layered compounds with composition ZrSxSe2-x, where x varies within the range 0-2, were grown by the chemical vapour transport technique using iodine as a transporting agent. These binary solid solution crystals are found to be isomorphous over the whole range of composition. The growth conditions and lattice parameters were determined. X-ray diffraction was employed to determine accurate lattice parameters. © 1995.
A new chelating polyelectrolyte for preconcentration and separation of trace metals employing resin-impregnated paper chromatography and determination by differential pulse anodic stripping voltammetry
(Springer-Verlag, 1995) B.B. Prasad; S. Sundd
A new chelate-forming polyelectrolytic resin bearing 5-sulfosalicylate counterions was prepared by an ion-exchange method. The resin was amorphous powder and therefore, batch method of separation endangered leaching of the ligand to the some extent. Nevertheless, the selective preconcentration and quantitative separation of Fe3+, Co2+, Cu2+ and Ni2+ were found to be feasible by employing chelating resin-impregnated paper chromatographic method, where separations involved a pH-independent differential migration procedure, based on solubility product equilibria, with aqueous mobile phases. The selectivity of resin for heavy metals, as monitored by differential pulse anodic stripping voltammetry, was found in the order Fe3+>Co2+>Ni2+≈Cu2+. © 1995 Friedr. Vieweg & Sohn Verlagsgesellschaft mbH.
Immunochemotherapy for a systemic intracellular infection: Accelerated response using interferon-γ in visceral leishmaniasis
(1995) Shyam Sundar; Frank Rosenkaimer; Martin L. Lesser; Henry W. Murray
To determine if cytokine immunotherapy accelerates the response to conventional treatment in visceral leishmaniasis (kala-azar), previously untreated Indian patients were given antimony for 30 days (n = 15) or antimony plus interferon-v (IFN-γ n = 16). After 10 days, 10 (63%) of 16 patients treated with antimony plus IFN-γ versus 1 (7%) of 15 randomized to antimony alone were considered cured of parasites (P <.005). On day 20, 14 (93%) of 15 versus 6 (40%) of 15 patients, respectively, were apparent clinical cures (P <.006), and treatment was discontinued early in the 14 IFN-γ-treated responders. Day 30 apparent cure rates (100% vs. 73%) and 6-month ultimate cure responses (87% vs. 60%) were higher in IFN-γ-treated patients but not statistically different from controls (P>.05). All 13 IFN-γ-treated subjects who were cured (12 of whom received therapy for 20 days) have remained healthy with follow-up of 14-24 months (mean, 18.9). These results indicate that IFN-γ successfully accelerates the parasitologic and clinical response to antimony treatment, an effect that should permit shortening the duration of conventional therapy in previously untreated kala-azar. © 1995, by The University of Chicago.
Effect of cations, including heavy metals, on cadmium uptake by Lemna polyrhiza L.
(Kluwer Academic Publishers, 1995) N. Noraho; J.P. Gaur
Cations, including calcium, magnesium, potassium, sodium, copper, iron, nickel and zinc, inhibited (up to 40%) extracellular binding and intracellular uptake of cadmium by Lemna polyrhiza in solution culture. Test plants showed a high capacity of extracellular cadmium binding which was competitively inhibited by copper, nickel and zinc; however, calcium, magnesium and potassium caused non-competitive inhibition. Iron and sodium increased Km and decreased Vmax, thereby causing mixed inhibition of extracellular binding. Intracellular cadmium uptake displayed Michaelis-Menten kinetics. It was competitively inhibited by calcium, magnesium, iron, nickel and zinc. Monovalent cations (sodium and potassium) caused non-competitive and copper caused mixed inhibition of intracellular cadmium uptake. Thus, high levels of cations and metals in the external environment should be expected to lower the cadmium accumulation efficiency of L. polyrhiza. © 1995 Rapid Communications of Oxford Ltd.
Microbial biomass associated with water-stable aggregates in forest, savanna and cropland soils of a seasonally dry tropical region, India
(1995) Saranath Singh; J.S. Singh
The distribution of microbial biomass associated with water-stable macro- and microaggregates in soils was studied along a forest-savanna-cropland gradient. In both macro- and microaggregates, mean microbial biomass C, N and P were maximum in forest and minimum in cropland soils. At all the sites microbial C was greater in the macroaggregate than the microaggregate size class, whereas microbial biomass N and P were greater in the microaggregates. The microbial C-to-nutrient ratios were lower for the microaggregates compared to macroaggregates. It is possible that these two size classes support two different types or components (fungi-dominated and bacteria-dominated) of the food web in soil. There was a decrease in the amount of microbial C, N and P in both macro- and microaggregates along the forest-savanna-cropland gradient, which was due to the reduction of total soil organic matter. Total soil organic C and total N showed significant positive relations with both macro- and microaggregate microbial C and N, indicating that the latter are limited by the quantity of soil organic matter. © 1995.
Analysis of local seismic events and inferred P* velocity near Koyna Dam, Maharashtra, India
(1995) A. Ram; R. Juneja; J.P. Narayan
Koyna region in Maharashtra, India got its place in the seismicity map of the world when a major shock occurred in this area on December 10, 1967. The seismic tremors were being monitored in this region with the seismological network operated by Central Water Power research Station (CWPRS), Poona since 1963. Four local seismological stations i.e. Koyna (KN), Satara (STA), Mahabaleshwar (MAH) and Poona (POO) were used as an array keeping KNI as crossover point. About 200 local events, which have occurred in this region and were recorded during the period 1967-1973, have been processed and analyzed using a least squares technique.
Neuroticism and stressful life events in patients with non-ulcer dyspepsia.
(1995) A.K. Jain; J.P. Gupta; S. Gupta; K.P. Rao; P.B. Bahre
Hindi adaptation of the Middlesex Hospital Questionnaire (MHQ), Brief Psychiatric Rating Scale and Presumptive Stressful Life Events Scale were used to measure neuroticism, psychiatric morbidity and stressful life events in 35 patients with non-ulcer dyspepsia (NUD), 22 cass of peptic ulcer disease (PUD), 65 irritable bowel syndrome (IBS) and 45 age and sex matched healthy controls. NUD subjects had significantly higher total MHQ scores (28.8 +/- 11.3; p < 0.001) and scores in subscales of somatization (7.8 +/- 3.4; p < 0.001) and hysterical personality traits (5.5 +/- 2.8; p < 0.01) compared to healthy controls. MHQ scores in IBS subjects was significantly higher than in NUD, but in PUD subjects it was in-between NUD and healthy controls. Psychiatric morbidity, as assessed by Brief Psychiatric Rating Scale, was significantly higher in patients with NUD and IBS than in normal controls. Stressful Life event score was statistically similar in all the groups.
Antioxidant and anti-inflammatory property of Sandhika: A compound herbal drug
(1995) S. Chaurasia; P. Tripathi; Y.B. Tripathi
The present study was envisaged to assess the rationality for the use of 'Sandhika', a popular Ayurvedic drug in rheumatoid arthritis. This drug, when tested against carrageenan induced paw oedema and cotton pellet granuloma, showed significant anti-inflammatory activity at the dose of 0.25 g/kg body weight. The antioxidant property was assessed by determining cumene hydroperoxide (CHP) induced lipid peroxidation and reduced glutathione content in rat liver homogenate (in vitro). Experiments show the significant protection against lipid peroxidation at the dose of 80 μg/ml, measured as reduction in the level of malondialdehyde (MDA) induced by 1.5 mM cumene hydroperoxide (CHP). This effect was accompanied by the maintained reduced glutathione (GSH) content in drug treated rats. Oral treatment of drug up to 2 g/kg body weight for 15 days did not show any rise in serum transaminases (SGOT and SGPT). The results suggest that 'Sandhika' which is an indigenous drug for inflammation with no detectable adverse effect, might be acting through scavenging the free radicals.
Cell cycle and DNA content of mitotic cells in brain ganglia of drosophila larvae
(Springer India, 1995) S.C. Lakhotia; J.K. Roy; Sujata kar Chowdhuri
The programmes of replication of hetero- and euchromatin regions, mitotic cell cycle and the DNA content in metaphases in brain ganglia from late third instar larvae of Drosophila melanogaster (wild type and a tumour bearing mutant, 1(2)gl, strain) and of Drosophila nasuta were examined by autoradiography of [3H]thymidine labelled (continuous or pulse) cells and by cytophotometry, respectively. Brain ganglia labelled continuously with [3H]thymidine for 24 h in vitro showed a significantly high proportion of cells with incorporation of radioactivity restricted to heterochromatin only. Pulse labelling of brain ganglia from larvae of Drosophila melanogaster and Drosophila nasuta followed by chase for different time intervals showed that (i) the frequency of labelled metaphases was more than 50% within 15 to 30 min of chase and remained higher than 50% in nearly all the chase samples till 24 h, (ii) euchromatin labelled metaphases appeared with a low frequency within 1 to 4 h chase period but the heterochromatin labelled metaphases continued to be more common in the later chase samples also, (iii) single chromatid labelled second cycle metaphases were seen within 1 to 4 h after the pulse, but their frequency did not increase in the later samples. Cytophotometry of feulgen-DNA and Hoechst 33258 stained metaphases in late third instar larval brain ganglia revealed a greater variation in the DNA content of individual metaphases, although the means were close to the expected 4 C content. It appears that in relation to the known asymmetric cell divisions of neuroblast and other neural cells, the mitotically active cells in brain ganglia comprise a heterogenous population with widely varying lengths of the different phases of cell cycle; some of them may not cycle regularly and may possibly have a discontinuous S-phase. © 1995 Indian Academy of Sciences.
Radiotracer technique in adsorption study-XI. Adsorption of barium and strontium ions on hydrous ceric oxide
(1995) Shuddhodan P. Mishra; Vinod K. Singh
Adsorption behavior of Ba and Sr ions on hydrous ceric oxide in aqueous solution has been studied as a function of concentration (10-2-10-7 M), temperature (303-333 K) and pH (7.24-11.42) of the adsorptive solution applying radiotracer technique. The kinetics of adsorption for both ions follows first-order rate law and agrees well with the classical Freundlich isotherm in the entire range of adsorptive concentration. The effect of temperature on the equilibrium adsorption values has been utilized to evaluate the change in standard thermodynamics quantities (viz. ΔH0, ΔG0 and ΔS0). Pre-irradiation of adsorbent with neutrons (3.85 × 106 n cm-2 s-1) and γ-radiations (ca 172 rad h-1) has practically no effect on the extent of adsorption for both the ions. The uptake process for both ions is found to be endothermic and irreversible in nature. © 1995.
Colonial dinosaur
(1995) S.S. Kushwaha
[No abstract available]
Theoretical Ne VI/Mg VI line diagnostics for SUMER
(Kluwer Academic Publishers, 1995) B.N. Dwivedi; Anita Mohan
Theoretical Ne vi/Mg vi EUV line emissivity ratios, suitable for density-measurements in various solar features such as active regions, sunspots, umbrae and flare plasmas and to be observed in the SUMER spectral range, are presented and their applications discussed with the help of available observational data. © 1995 Kluwer Academic Publishers.
Vitamin a administration and preschool child mortality
(1995) D.K. Agarwal; C.M. Pandey; K.N. Agarwal
A double blind study conducted during January 90-March 91 in a rural part of Varanasi district in Uttar Pradesh state of India on 9987 and 5260 children under six years of age demonstrated that administration of vitamin A reduced overall mortality by 14.0%. The additional data collected from January 1991 to February 92 under similar settings on 1314 and 1200 children of same age in the experimental and control groups respectively and from all children suffering from xerophthalmia who received mega dose of vitamin A (200,000 I.U.), taken together, show that vitamin A supplementation results in 16.9% reduction in mortality. Mortality was reduced in unimmunized children by 22.0%, diarrhea by 18.8% and measles by 9.0%. However, significant reduction in mortality in vitamin A supplemented group was observed only for deaths due to severe malnutrition. No death was recorded in xerophthalmia children who received mega dose of vitamin A (200,000 I.U.). The child survival pattern remained unaltered and mortality pattern remained unchanged significantly even after one year of withdrawal, thus denying the possibility of any substantial change in the study area for births and deaths. Thus the finding that vitamin A supplementation protects against overall mortality and in particular deaths due to gastroenterits, severe malnutrition and in unimmunized children is of significance. © 1995.
Functional maturation of neuroendocrine gonadal axis is altered by specific phase relations of circadian neurotransmitter activity in Japanese quail.
(1995) D. Phillips; C.M. Chaturvedi
The present study was designed to ascertain the effects of temporal relationship of circadian neural oscillations on puberty attainment and reproductive growth of Japanese Quail, Coturnix coturnix japonica. Serotonin and dopamine precursors (5-hydroxytryptophan, 5-HTP and L-dihydroxyphenylalanine, L-DOPA; 5 mg/100 g body weight) were injected daily, 8 and 12 h apart in two groups of one-day old chicks, while controls received two daily injections of normal saline. Weekly/biweekly observations (body weight, cloacal gland size, testicular volume and activity, ovarian follicular diameter and rate of egg production) were made until 9 weeks of age, when the experiment was terminated. Results indicate that 8 h relationship completely suppressed gonadal growth even under long photoperiod (LD 16:8), while a 12 h relationship induced precocious sexual maturity and increased the rate of reproduction (spermatogenesis and egg production). It is concluded that circadian phase relationship of serotonergic and dopaminergic activity may not only determine the onset of reproduction in this poultry species, but may also alter the rate of reproduction possibly by affecting photoperiodic mechanism of reproductive regulation.
Effects of endosulfan on bioenergetic properties of skeletal muscle mitochondria from the freshwater catfish (Clarias batrachus)
(1995) Rajnikant Mishra; S.P. Shukla
The effects of a sublethal concentration of an organochlorine pesticide endosulfan on fish skeletal muscle mitochondria oxidizing isocitrate and succinate in vivo and in vitro were investigated. The endosulfan depressed significantly State 3 rates and RCR with succinate, whereas it prevented completely the oxidation of isocitrate. The CCCP-uncoupled rates and State 4 rates of succinate oxidation remained unaffected by endosulfan. The activity of masked ATPase was significantly increased in presence of endosulfan. There was a progressive stimulatory effect of endosulfan on mitochondrial ATPase. The skeletal muscle fibres of endosulfan exposed fish undergo ultrastructural changes that are characterized by deformation of the myofibrils and disappearance of mitochondria. Summarizing, it can be stated that endosulfan exerts an inhibitory effect on electron transport and affects ATP synthetase complex leading to an impairment in mitochondrial bioenergetics, which can be correlated with marked ultrastructural alterations in the skeletal muscle fibres of the fish. © 1995.
Spectroscopic and Biochemical Analyses of UV Effects on Phycobiliproteins of Anabaena sp. and Nostoc carmium
(1995) R.P. Sinha; M. Lebert; A. Kumar; H.D. Kumar; D.‐P. Häder
The effects of UV (280–400 nm) irradiation on phycobiliprotein composition have been studied in two N2‐fixing cyanobacteria, Anabaena sp. and Nostoc carmium, isolated from rice paddy fields in India. Phycobiliproteins were isolated and separated by sucrose density gradient centrifugation. After UV exposure the top fraction mainly contained carotenoids (absorption maximum at 485 nm), which first showed an increase in intensity and absorption and then a gradual decrease with increasing UV exposure in Anabaena sp., whereas, in Nostoc carmium this fraction showed a steady increase over the whole exposure time. The bottom fraction of both organisms mainly contained phycocyanin (absorption peak at 620 nm) which showed a steady decline in intensity, as well as absorption. Fluorescence excitation at 620 nm resulted in an emission at 650 nm which underwent a shift towards shorter wave‐lengths with increasing UV‐exposure time, indicating a disassembly of the phycobilisomal complex and of impaired energy transfer from accessory pigments to the reaction centers. SDS PAGE analysis of the fractions revealed a loss of high molecular mass linker proteins and low molecular mass (αβ monomers indicating that the phycobiliproteins, which function as accessory pigments for the operation of photosystem II, disassemble during UV irradiation. 1995 Deutsche Botanische Gesellschaft/German Botanical Society